Multilayer substrate and electronic device

Abstract

In a first region, a multilayer body is bent along a first bending line such that a first main surface is located farther on an outer peripheral side than a second main surface. In a second region, the multilayer body is bent along a second bending line such that the first main surface is located farther on an inner peripheral side than the second main surface. In the first region, a first metal foil layer is located farther on an outer peripheral side than a center of the multilayer body. In the second region, a second metal foil layer is located farther on the outer peripheral side than the center of the multilayer body. In the second region, a distance between the second metal foil layer and the second main surface is shorter than a distance between the second metal foil layer and the first main surface.

What is claimed is: 
     
       1. A multilayer substrate comprising:
 a multilayer body including a plurality of insulating layers laminated together, and a first main surface and a second main surface arranged in a laminating direction of the plurality of insulating layers; 
 a first metal foil layer provided in the multilayer body and including a main surface on which a plurality of streaks extending in a first direction, when viewed in the laminating direction, is provided; and 
 a second metal foil layer provided in the multilayer body and including a main surface on which a plurality of streaks extending in a second direction, which is different from the first direction, when viewed in the laminating direction, is provided; wherein 
 the multilayer body includes a first region in which the multilayer body is bent along a first bending line such that the first main surface is located farther on an outer peripheral side than the second main surface, and a second region in which the multilayer body is bent along a second bending line such that the first main surface is located farther on an inner peripheral side than the second main surface; 
 the second bending line is not parallel to the first bending line; 
 in the first region, the first metal foil layer is located farther on an outer peripheral side than a center of the multilayer body in the laminating direction; 
 in the second region, the second metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the first direction and the first bending line is larger than an angle defined by the first direction and the second bending line; and 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the second direction and the second bending line is larger than an angle defined by the second direction and the first bending line. 
 
     
     
       2. The multilayer substrate according to  claim 1 , further comprising:
 a third metal foil layer provided in the multilayer body and including a main surface on which a plurality of streaks extending in a third direction, when viewed in the laminating direction, is provided; wherein 
 in the first region, the third metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; and 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the third direction and the first bending line is larger than an angle defined by the third direction and the second bending line. 
 
     
     
       3. The multilayer substrate according to  claim 2 , further comprising:
 a fourth metal foil layer provided in the multilayer body and including a main surface on which a plurality of streaks extending in a fourth direction, when viewed in the laminating direction, is provided; wherein 
 in the second region, the fourth metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; and 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the fourth direction and the second bending line is larger than an angle defined by the fourth direction and the first bending line. 
 
     
     
       4. The multilayer substrate according to  claim 3 , wherein a surface roughness of the main surface of the first metal foil layer and a surface roughness of the main surface of the second metal foil layer are smaller than a surface roughness of the main surface of the third metal foil layer. 
     
     
       5. The multilayer substrate according to  claim 3 , wherein a surface roughness of the main surface of the first metal foil layer and a surface roughness of the main surface of the second metal foil layer are larger than a surface roughness of the main surface of the third metal foil layer. 
     
     
       6. The multilayer substrate according to  claim 2 , wherein the third metal foil layer is a signal conductor layer through which a signal is transmittable. 
     
     
       7. The multilayer substrate according to  claim 1 , wherein
 the multilayer body includes a third region in which the multilayer body is bent along a third bending line such that the second main surface is located farther on the outer peripheral side than the first main surface; 
 in the third region, the second metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the second direction and the third bending line is smaller than the angle defined by the second direction and the second bending line; and 
 a curvature radius of the third region is larger than a curvature radius of the first region. 
 
     
     
       8. The multilayer substrate according to  claim 7 , wherein
 the multilayer body further includes a fourth region in which the multilayer body is bent along a fourth bending line such that the first main surface is located farther on the outer peripheral side than the second main surface; 
 in the fourth region, the first metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the first direction and the fourth bending line is smaller than the angle defined by the first direction and the first bending line; and 
 a curvature radius of the fourth region is larger than a curvature radius of the second region. 
 
     
     
       9. The multilayer substrate according to  claim 1 , wherein
 the multilayer body includes a third region in which the multilayer body is bent along a third bending line such that the second main surface is located farther on the outer peripheral side than the first main surface; 
 in the third region, the second metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the second direction and the third bending line is smaller than the angle defined by the second direction and the second bending line; and 
 a curvature radius of the third region is larger than a curvature radius of the second region. 
 
     
     
       10. The multilayer substrate according to  claim 9 , wherein
 the multilayer body includes a fourth region in which the multilayer body is bent along a fourth bending line such that the first main surface is located farther on the outer peripheral side than the second main surface; 
 in the fourth region, the first metal foil layer is located farther on the outer peripheral side than the center of the multilayer body in the laminating direction; 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, an angle defined by the first direction and the fourth bending line is smaller than the angle defined by the first direction and the first bending line; and 
 a curvature radius of the fourth region is larger than a curvature radius of the first region. 
 
     
     
       11. The multilayer substrate according to a  claim 1 , wherein the first metal foil layer and the second metal foil layer are reference conductor layers connected to a reference potential. 
     
     
       12. The multilayer substrate according to  claim 1 , wherein at least one of a thickness of the multilayer body in the laminating direction in the first region or a thickness of the multilayer body in the laminating direction in the second region is smaller than a thickness of the multilayer body in the laminating direction at least in a portion of a region excluding the first region and the second region. 
     
     
       13. An electronic device comprising the multilayer substrate according to  claim 1 . 
     
     
       14. A multilayer substrate comprising:
 a multilayer body including a plurality of insulating layers laminated in a laminating direction; 
 a first metal foil layer provided in the multilayer body and including a main surface on which a plurality of streaks extending in a first direction, when viewed in the laminating direction, is provided; and 
 a second metal foil layer provided in the multilayer body and including a main surface on which a plurality of streaks extending in a second direction, which is different from the first direction, when viewed in the laminating direction, is provided; wherein 
 the multilayer body is bent in the laminating direction. 
 
     
     
       15. The multilayer substrate according to  claim 14 , wherein
 the multilayer body includes a first region in which the multilayer body is bent along a first bending line, and a second region having a structure in which the multilayer body is bent along a second bending line; and 
 the second bending line is not parallel to the first bending line. 
 
     
     
       16. The multilayer substrate according to  claim 15 , wherein
 the multilayer body includes a first main surface and a second main surface arranged in the laminating direction of the plurality of insulating layers; 
 the first region has a structure in which the multilayer body is bent along the first bending line such that the first main surface is located farther on an outer peripheral side than the second main surface; 
 in the first region, the first metal foil layer is located farther on an outer peripheral side than a center of the multilayer body in the laminating direction; and 
 in a state in which the multilayer body is shown on a plane, when viewed in the laminating direction, the first direction intersects with the first bending line. 
 
     
     
       17. The multilayer substrate according to  claim 15 , wherein at least one of a thickness of the multilayer body in the laminating direction in the first region or a thickness of the multilayer body in the laminating direction in the second region is smaller than a thickness of the multilayer body in the laminating direction at least in a portion of a region excluding the first region and the second region. 
     
     
       18. The multilayer substrate according to  claim 14 , wherein a surface roughness of the main surface of the first metal foil layer and a surface roughness of the main surface of the second metal foil layer are smaller than a surface roughness of the main surface of the third metal foil layer. 
     
     
       19. The multilayer substrate according to  claim 14 , wherein the first metal foil layer and the second metal foil layer are reference conductor layers connected to a reference potential. 
     
     
       20. An electronic device comprising the multilayer substrate according to  claim 14 .